This is the next chapter in a multi-part Shingles series originally prompted by an obscure link to Red Ear Syndrome.  That link lead to posts on shingles in general, shingles in the ear, and the specifically-named Ramsay-Hunt Syndrome Type 2 (RHS/2) .

RHS/2 is a horribly painful condition in which the herpes zoster in the geniculate ganglion reactivates and manifests in any number of ways, including deafness, vertigo, pain, and facial weakness/paralysis. RHS/2 is difficult to diagnose and distinguish from other problems. For example, it is almost always characterized by a severe rash but it can also occur with facial paralysis without a rash, similar to Bell’s palsy and that’s what today’s post is about.  

 

What’s an Erythematous Vesicular Rash? What Does it Mean?

 

This rash is like Supreme Court Justice Potter Stewart’s famous definition of obscenity–you know it when you see it.  In this case, you definitely know it when you feel it because of the extreme pain.  Erythematous vesicular rash affects skin as well as mucous membranes, such as the lining of the mouth. It is characterized by

large, symmetrical red blotches [which] appear all over the skin in a circular pattern. On mucous membranes, it begins as blisters and progresses to ulcers.”

The problem with this rash is that it can be caused by a variety of things (e.g., medications) that have nothing to do with Ramsay Hunt or infection of any kind. For example, it can be misdiagnosed as a kissing bug bite (which raises the spectre of Chagas disease), based on the presence of vesicular rash by the lip.  Even more of a problem is that RHS/2 can occur without any rash anywhere, a situation referred to as “sine herpete” in the medical literature.

The presence or absence of  facial erythematous vesicular rash is not diagnostic for RHS/2, though its presence surely should gain the attention of the physician and its absence in the presence of facial paralysis should not rule out RHS/2.

 

All in the (Herpes) Family

 

We’ve tried to make this series clear and simple, but the anatomy and physiology have defeated our efforts.  Just talking about the geniculate ganglion takes us places we never went in hearing and speech anatomy classes.  The varicella zoster virus (VZV) and its cousin herpes simplex virus (HSV) are better versed in the anatomical pathways than we are. Once unleashed, they seem to ride those pathways like highways, taking little-known, interconnected neural shortcuts as they please.  Pulling it all together, as best we can, here’s a brief summary of what the zosters can get up to:

  • HZ oticus Just the ear.  Caused by VZV in the geniculate ganglion.  Herpes zoster oticus affects any/all parts of the peripheral ear:  external (pinna, ear canal, eardrum), middle, and inner (cochlea).  It causes severe ear pain associated with vesicular rash.  Hearing loss, if present, varies in severity and permanence.
  • RHS/2.  The ear and the face.  Caused by VZV in the geniulate ganglion. When HZ oticus is accompanied by facial paralysis, it becomes  Ramsay Hunt syndrome.   Just to confuse things, we noted in our last post on this subject that strictly speaking, you can have RHS/2 without any signs in the ear, in which case it’s RHS/2 without herpes zoster oticus.  Confusing.  But most of the time the ear’s involved so herpes zoster oticus is frequently referred to simply as Ramsay-Hunt.
  • RHS/2 sine herpete.  The ear and the face, but no rash.  This is confusing.  There is no rash (sine herpete) but there is facial paralysis and other symptoms, some involving the ear.  Caused by VZV in the geniculate ganglion.
  • Bell’s palsy (also called Bell palsy).  Facial paralysis/weakness, no rash.  Unlike HZ oticus and Ramsay-Hunt, Bell’s palsy is thought to be caused by herpes simplex virus (HSV) type I infection in the geniculate ganglion, NOT by VZV.  Bell’s palsy is staged according to degree of facial weakness from Stage I (normal facial function) to Stage VI (total single-sided facial paralysis).Facial paralysis in RHS/2 may be more severe and lasting than that of Bell’s palsy, though that probably depends on the Stage of Bell’s palsy.  You can imagine, though, that RHS/2 sine herpete and Bell’s palsy are easily confused — both show facial paralysis/weakness, neither shows a rash. And just to confuse things even more, Bell’s palsy can paralyze the muscles of the middle ear, effecting the same result as some forms of HZ oticus.  Blood tests can distinguish which virus (VZV or HSV) is present.

The bottom line for audiologists is that a complete audiometric workup is necessary for patients who present initially or upon return, with complaints of sudden-onset unilateral ear pain, hearing loss, dizziness, facial paresis or rash.  As soon as testing is completed,  send the patient–audiogram in hand–for ASAP workup by their physician or an ENT, with the goal of arriving at a diagnosis and treatment as quickly as possible.  In many cases, early treatment can mitigate symptoms and reduce long-term effects.

What diagnoses are made or ruled out when patients are worked up medically?  We’ll look at some case histories and competing diagnoses when we next write about Shingles in this series.

feature image from Mayo Clinic

Today’s post continues a Shingles series that started with an obscure link to Red Ear Syndrome.  That link lead to posts on shingles in general and shingles in the ear.  The latter co-mingles with the specifically-named Ramsey-Hunt syndrome, pictured horrifically above, the subject of the next several posts in this series.  

 

RHS is a Confusing Bundle of Syndromes

 

Despite a specific-sound name, Ramsay Hunt Syndrome (RHS) is a nebulous term that causes diagnostic irritability (e.g., authors of  “Ramsay Hunt Syndrome: To Bury or to Praise”  voted to bury it!).  That’s because RHS covers totally separate neurological syndromes  bunched together for no good reason other than  they were discovered by the eminent 20th century neurologist Dr. James Ramsay Hunt (1872-1937).  Too bad for Dr. Hunt, who seems to have been a good guy, to be remembered chiefly for a horribly painful condition and for totally confusing the medical literature.

Three syndromes comprise RHS:

  1. Ramsay Hunt type 1:  “rare, degenerative, neurological disorder characterized by myoclonus epilepsy, intention tremor, progressive ataxia and occasionally cognitive impairment .”   NOT  in Audiology’s Scope of Practice.
  2. Ramsay Hunt type 3:  “occupationally induced neuropathy of the deep palmar branch of the ulnar nerve… also called Artisan’s palsy.”   This type is so obscure that it doesn’t even have it’s own write-up on Wikipedia and Artisan’s palsy is not a valid Scrabble word. Way outside our Scope of Practice.
  3. Ramsay Hunt type 2:  Herpes zoster oticus.  This is the one for which Dr Ramsay Hunt is  famous and the one that has to do with Audiology. RHS/2 is the “reactivation syndrome of herpes zoster in the geniculate ganglion. It has variable presentation which may include Bell’s palsy, deafness, vertigo, and pain.”  

 

What’s the Geniculate Ganglion?

 

Figure 1. Auditory nerve, vestibular nerve, and facial nerve Bunched Together to Enter and Exit the brainstem.  Facial Nerve branch enters from the geniculate body.

Readers who’ve been following this series are right to ask, since that anatomical term didn’t surface in previous discussion of shingles, the ear, or the ear-brain neural connections.  Figure 1 illustrates all that’s packed into the internal auditory canal, which is a lot.

The geniculate ganglion sits up at a fork in the road in Figure 1, where the nerves enter or leave the brain on their way to and from the ear.  It’s the same bottleneck where all our vestibulocochlear nerve problems seem to hang out.  What a mess.

The facial nerve (CVII) sends a sensorimotor branch down through the canal, sandwiched in with the hearing and balance nerves and blood supply to the inner ear.  The intersection for that branch and others on the Facial nerve is the geniculate body, which serves as central headquarters for facial muscle movement,  touch sensation in the ear canal and parts of outer ear,  taste on  much of the tongue, and eye and mouth moisturizing.  

So many things in such a tiny area — so many ways to go wrong.

 

Ramsay Hunt Type 2 (RHS/2):  With Herpes Zoster Oticus Most of the Time

 

In RHS/2, the varicella zoster virus lives in the geniculate body and becomes RHS/2 upon re-awakening — “following” the facial nerve.  The vestibulocochlear nerve is in such close proximity to the geniculate ganglion that it’s usually affected as well.  The strict definition of the RHS Type 2 is “peripheral facial nerve palsy accompanied by an erythematous vesicular rash on the ear (zoster oticus) or in the mouth” (more on that in the next post).  

Right away, you can see the confusion:  strictly speaking, you can have RHS/2 without any signs in the ear, in which case it’s RHS/2 without herpes zoster oticus.  Confusing.  But most of the time the ear’s involved so herpes zoster oticus is frequently referred to simply as Ramsay Hunt.

RHS/2 often begins with paroxysmal (sudden, stabbing) pain deep in the ear that moves out to the pinna and transitions to a constant, dull and diffuse pain within several days.  From start to finish, all sorts of symptoms are possible, though not all symptoms happen to everyone affected:

  •  Painful rash
    • ear, ear canal, ear drum
    • lower face
    •  mouth:  hard palate,  tongue
    • neck, and/or scalp
  • Intense ear pain
  •  Unilateral hearing loss
  • Unilateral hyperacusis (increased sensitivity to loud sounds)  due to paralysis of the stapedius and tensor tympani muscles of the ear
  •  Nystagmus (eyes twitch back and forth or up and down in tandem)
  •  Vertigo
  • Vomiting
  •  Tinnitus
  •  Acute facial nerve paralysis or facial weakness
  •  Loss of taste in front 2/3’s  of the tongue
  • Dry mouth
  • Dry eyes
  • Malaise
  • Fever

With that many symptoms manifesting in a variety of ways, it is no wonder that diagnosing  RHS/2 can be problematic.  The diagnosis is even more challenging when there is no rash present (yes, that can happen).  In that case, Bell’s palsy and RHS/2 are hard to tell apart, but it is important to do so.  Next post in this series will look at the rash and continue the Ramsay Hunt story.

 

References

 

References are accessible by clicking on the links in the post.  The following reference was used for general information scattered throughout the post:

 Sartoretti-Schefera S, et al.  Ramsay Hunt Syndrome Associated with Brain Stem Enhancement.  AJNR 1999 20: 278-280.